Don't use header_libs for musl crt objects

Bazel considers the musl crt objects depending on a header lib
to be a circular dependency (toolchain -> crt objects -> header
lib -> toolchain).  Make a copy of the headers in the crt defaults
instead of using the header libs.

Bug: 259266326
Bug: 263407827
Test: USE_HOST_MUSL=true build/bazel/ci/mixed_libc.sh
Test: m USE_HOST_MUSL=true
Change-Id: I6d1747e8b582e92daefda2384593164bf4ec19ea
1 file changed